Presently, shower valves or taps used in bathroom have cold water and hot water separated. The flow of the cold water and the hot water is controlled by valve openness. The wider the valve is opened, the bigger the water flow is. The narrower the valve is opened, the smaller the flow is. Pressure will be generated when water flows out, exerting an impact on each valve. These valves are rigid and have no buffering function. When the valve is opened, the surge of water flow will impact the valve, thus shortening the service life of the valve. Since there is no buffer unit, when cold/hot water is adjusted, some water will flow back. For example, hot water may flow back to join the hot water behind, and may flow back to the location of the cold water pipe, causing partial pollution. Without a buffer unit, water at a high temperature sprays out from the tap at a high speed, which is unpredictable and can easily cause burns to a user. So it is dangerous in operation.
China Intellectual Property Office published Patent No. CN201232801Y on May 6, 2009, which is related to an embedded unit of tap body including an embedded box and a lower body. The lower body is fixed in the embedded box. Two or more water pipelines are arranged. One end of the pipeline penetrates through the lateral wall of the embedded box. The other end forms a through hole on an upper surface of the lower body. However, this device is not provided with a buffer unit, so the high-pressure hot water will directly eject from the tap, which is unpredictable. Besides, the scope of water flow dispersion becomes narrower and narrower after the pressure has dropped, so a user needs to adjust the valve to control the scope of water flow dispersion. The rigid structure also causes backflow of the water.